> ## Documentation Index
> Fetch the complete documentation index at: https://braintrust.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# ElevenLabs

> Trace ElevenLabs SDK calls in Braintrust to debug audio generation, evaluate models, and monitor production usage

[ElevenLabs](https://elevenlabs.io/) is a voice AI platform providing text-to-speech and speech-to-text. Braintrust traces ElevenLabs SDK calls, including speech generation, streaming audio, timestamped audio, and transcription.

<View title="TypeScript" icon="/images/sdk-icons/typescript.svg">
  <h2 id="setup-typescript">
    Setup
  </h2>

  Install the Braintrust and `@elevenlabs/elevenlabs-js` packages, then set your API keys. Requires `@elevenlabs/elevenlabs-js` v2.67.0 or later.

  <Steps>
    <Step title="Install packages">
      <CodeGroup>
        ```bash pnpm theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}}
        pnpm add braintrust @elevenlabs/elevenlabs-js
        ```

        ```bash npm theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}}
        npm install braintrust @elevenlabs/elevenlabs-js
        ```
      </CodeGroup>
    </Step>

    <Step title="Set environment variables">
      ```bash title=".env" theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}}
      BRAINTRUST_API_KEY=<your-braintrust-api-key>
      ELEVENLABS_API_KEY=<your-elevenlabs-api-key>

      # For organizations on the EU data plane, use https://api-eu.braintrust.dev
      # For self-hosted deployments, use your data plane URL
      # BRAINTRUST_API_URL=<your-braintrust-api-url>
      ```
    </Step>
  </Steps>

  <h2 id="auto-instrumentation-typescript">
    Auto-instrumentation
  </h2>

  To trace ElevenLabs SDK calls without modifying your application code, initialize Braintrust normally, then run your app with Braintrust's import hook to patch the ElevenLabs SDK at runtime.

  <Steps>
    <Step title="Initialize Braintrust and call ElevenLabs">
      <CodeGroup>
        ```javascript title="trace-elevenlabs-auto.js" theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}}
        import { initLogger } from "braintrust";
        import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js";

        initLogger({
          projectName: "elevenlabs-example",
          apiKey: process.env.BRAINTRUST_API_KEY,
        });

        const client = new ElevenLabsClient({
          apiKey: process.env.ELEVENLABS_API_KEY,
        });

        const audio = await client.textToSpeech.convert(
          "<voice-id>", // Replace with your ElevenLabs voice ID
          {
            text: "Braintrust traces all your AI calls.",
            modelId: "eleven_flash_v2_5",
          },
        );

        for await (const chunk of audio) {
          // process audio chunk
        }
        ```
      </CodeGroup>
    </Step>

    <Step title="Run with the import hook">
      ```bash theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}}
      node --import braintrust/hook.mjs trace-elevenlabs-auto.js
      ```

      The auto-instrumentation example uses plain JavaScript so `node --import` can run the file directly. The Braintrust APIs work the same in TypeScript projects — compile your TypeScript to JavaScript, then run the compiled file with the import hook.

      <Note>
        If you're using a bundler, see [Trace LLM calls](/docs/instrument/trace-llm-calls#auto-instrumentation) for plugin and loader setup.
      </Note>
    </Step>
  </Steps>

  <h2 id="manual-instrumentation-typescript">
    Manual instrumentation
  </h2>

  To trace ElevenLabs clients manually, wrap them yourself with `wrapElevenLabs()`. Use this when you want to instrument specific clients individually rather than all of them globally.

  <CodeGroup>
    ```javascript JavaScript theme={"theme":{"light":"github-light","dark":"github-dark-dimmed"}}
    import { initLogger, wrapElevenLabs } from "braintrust";
    import { ElevenLabsClient } from "@elevenlabs/elevenlabs-js";

    initLogger({
      projectName: "elevenlabs-example",
      apiKey: process.env.BRAINTRUST_API_KEY,
    });

    const client = wrapElevenLabs(
      new ElevenLabsClient({
        apiKey: process.env.ELEVENLABS_API_KEY,
      }),
    );

    const audio = await client.textToSpeech.convert(
      "<voice-id>", // Replace with your ElevenLabs voice ID
      {
        text: "Braintrust traces all your AI calls.",
        modelId: "eleven_flash_v2_5",
      },
    );

    for await (const chunk of audio) {
      // process audio chunk
    }
    ```
  </CodeGroup>

  <h2 id="what-traced-typescript">
    What Braintrust traces
  </h2>

  Braintrust patches the `@elevenlabs/elevenlabs-js` SDK and creates an LLM-typed span per call:

  * Text-to-speech spans (`elevenlabs.textToSpeech.convert`): input text, voice ID, and model as metadata. Generated audio is attached as a Braintrust attachment with content type `audio/mpeg`.
  * Streaming text-to-speech spans (`elevenlabs.textToSpeech.stream`): same as above, with `time_to_first_token` captured for the first audio chunk.
  * Timestamped text-to-speech spans (`elevenlabs.textToSpeech.convertWithTimestamps`, `elevenlabs.textToSpeech.streamWithTimestamps`): same fields as their non-timestamped counterparts, including word-level timing data.
  * Transcription spans (`elevenlabs.speechToText.convert`): audio input and model as metadata. Transcript text is captured as output.
  * Errors captured on every call.

  <Note>
    Webhook transcription and Speech Engine sessions are not instrumented.
  </Note>

  <h2 id="resources-typescript">
    Resources
  </h2>

  * [ElevenLabs JavaScript SDK](https://github.com/elevenlabs/elevenlabs-js).
  * [ElevenLabs API reference](https://elevenlabs.io/docs/api-reference).
</View>